WonderSwan Color Console - With Defects

WonderSwan Color with Color LCD Display

Confirmed to power on.
Volume adjustment also works without issue.
The device powers on and plays games normally, but for some reason, the power button does not work when turning it off.
Therefore, to turn it off, I have to forcibly remove the batteries.
I've seen online that this issue can be repaired, so I hope someone can make good use of it.
Additionally, while the Detective Conan software can be played, I was unable to confirm if the Inuyasha software boots up.
I will include it as a bonus, but please understand and accept this condition.

- Model Name: WonderSwan Color
- Screen: Color LCD
- Country of Manufacture: Japan

Thank you for looking.